Method of manufacturing honeycomb body

ABSTRACT

The present invention provides a method of manufacturing a honeycomb body ( 1 ) formed by winding a flat metal foil ( 3 ) and a corrugated metal foil ( 4 ) in layers and brazing them, capable of reducing the equipment cost of honeycomb body manufacturing facilities and conforming to the countermeasure against an engine misfire problem of the honeycomb body, without causing insufficient or excessive application of adhesive which is seen in the cases of adhesive application methods using rolls; and relates to a method of manufacturing a honeycomb body characterized by: applying an adhesive to the portions to be brazed of the flat or corrugated foil corresponding to a bonding portion ( 17 ) which is located at one or both ends of the honeycomb body and/or a bonding portion ( 18 ) inside the honeycomb body over a cross section which is located away from one or both ends thereof in the axial direction; then, winding the flat and corrugated foils in layers to form a honeycomb body; then, making the portion of one or both end faces of the honeycomb body corresponding to the bonding portion ( 16 ) over the full axial length of the honeycomb body outer layers contact the surface of a liquid binder and having the binder sucked up along contact lines ( 5 ) of the flat and corrugated foils; and, then, feeding a brazing filler metal in powder to the honeycomb body so as to have it deposited at the portions where the adhesive and binder have been deposited.

TECHNICAL FIELD

The present invention relates to a method of manufacturing a honeycombbody formed by winding a flat metal foil and a corrugated metal foil,one over the other, and brazing them, especially a metal honeycomb bodyused as a catalyst support for purifying automobile emission gas and thelike.

BACKGROUND ART

A catalyst converter holding a catalyst is installed in an emission gaspath of an internal combustion engine for the purpose of purifying theemission gas. A support holding a catalyst is used likewise also in amethanol reforming apparatus to generate hydrogen-rich gas by steamreforming of hydrocarbon compounds such as methanol, a CO removalapparatus to reform CO into CO₂ to remove it, and a hydrogen combustionapparatus to burn H₂ into H₂O to remove it. A catalyst support iscomposed of many cells through which gas passes, and the wall surface ofeach of the cells is coated with a catalytic materials so as to havethe-gas passing through the cells contact with the catalytic materialsin a large contact area.

Either a ceramic catalyst support or a metal catalyst support is used asa catalyst support for the above purposes. The metal catalyst support ismanufactured by winding a flat foil and a corrugated foil of a heatresistant alloy of several tens micrometers in thickness in layers, oneover the other, to form a cylindrical metal honeycomb body, and encasingthe metal honeycomb body in a cylindrical metal jacket. The honeycombbody is turned into a catalyst support by forming a catalyst holdinglayer impregnated with a catalytic materials on the wall surfaces of thehoneycomb body cells through which the gas passes. The contact lines ofthe flat and corrugated foils of the honeycomb body formed throughwinding the foils are bonded by brazing or a similar bonding method ofmaking the honeycomb body a strong structure.

A catalyst support used for purifying automobile emission gas issubjected to a violent thermal load during acceleration or high speedcruising of a vehicle as a result of high temperature emission gaspassing through it. On the other hand, when an engine is idling or it isstopped, emission gas of a comparatively low temperature passes throughit. Thus, heat cycles from high temperatures to low temperatures arerepeated on the catalyst support and, therefore, a high structuralreliability to withstand severe thermal stress and fatigue is requiredas the honeycomb body composing the catalyst support.

When a catalyst support is subjected to heating and cooling, a largetemperature difference takes place between the center portion and theperipheral portion of the honeycomb body constituting the support: whenthe center portion is heated to a temperature higher than that of theperipheral portion, the center portion expands and, as a result, theperipheral portion undergoes a compressive stress; and when the centerportion is cooled to a temperature lower than that of the peripheralportion, on the other hand, the center portion contracts and theperipheral portion is subjected to a tensile stress. Thus a largethermal stress is imposed on the peripheral portion in either case.

As shown in FIG. 2(a), Japanese Patent No. 2732889 and Japanese ExaminedPatent Publication No. H5-45298 disclose, inventions to bond a flat foil3 and a corrugated foil 4 along their contact lines at a bonding portion16 over the full axial length of the honeycomb body outer layers 12 forthe purpose of preventing the fracture of the honeycomb body against thelarge thermal stress generated near its periphery, and to bond the foilsonly at a part of the axial length of the honeycomb body inner layers 13(the layers other than the outer layers 12), more specifically only at abending portion 17 which is located at the gas inlet end of thehoneycomb body, for the purpose of minimizing the generated thermalstress as much as possible. Japanese Patent No. 2512622 discloses, asshown in FIG. 2(b), a honeycomb body in which the flat and corrugatedfoils are bonded only at a part of the prescribed axial length of thehoneycomb body (a bonding portion 18 inside the honeycomb body over across section) and the foils are bonded also in the axial direction atthe portion of the outermost 5 layers or less (a bonding portion 16 overthe full axial length of the honeycomb body outer layers) for the samepurpose.

When an automobile engine misfires, unburned gas combusts at the midstof honeycomb body and the temperature of the foils inside the honeycombbody exceeds their melting point. In the case of the above inventionswherein the foils are bonded only at the gas inlet end of the honeycombbody excluding the outer layers of the honeycomb body as shown in FIG.2(a), if the foils melt inside the honeycomb body as a result of themisfire, the foils may protrude from the honeycomb body. JapaneseRegistered Utility Model No. 2543636 discloses, as shown in FIG. 2(c), ametal catalyst support free from the problem of protrusion of thehoneycomb body or the like, wherein the flat and corrugated foils arebonded not only at the bonding portion 17 which is located at the gasinlet end of the honeycomb body but also at another bonding portion 18inside the honeycomb body over a cross section which is located awayfrom both ends thereof in the axial direction, as well as at the bondingportion 16 over the full axial length of the honeycomb body outer layersfor the purpose of supporting the foils by the bonding portion 18 overthe cross section even when the foils melt inside the honeycomb body asa result of a misfire.

In the above inventions wherein the flat foil 3 and the corrugated foil4 constituting the honeycomb body are brazed only at a part or partsalong their contact lines, a brazing filler metal is deposited only atthe portions to be brazed and then the honeycomb body is heated to ahigh temperature to have the filler metal melt to braze those depositedparts of the contact lines of the flat and corrugated foils.

As a method of depositing the brazing filler metal only to the selectedportions of the flat and corrugated foils, Japanese UnexaminedInternational Patent Application No. H3-501363 discloses a method ofapplying an adhesive or a binding material to the areas to be brazed ofany one of the flat and corrugated foils before winding them, then windthem in layers and feed the brazing filler metal in powder into thewound support, for the purpose of depositing it at the areas where theadhesive has been applied.

As a method of applying an adhesive to the areas to be later brazed of aflat or corrugated foil, Japanese Unexamined Patent Publication No.S56-4373 discloses a method of supplying an adhesive from an adhesivestorage tank to the surface of a roll and applying the adhesive to thesurface of a flat or corrugated foil by way of the roll.

At the contact lines of the flat and corrugated foils in a honeycombbody, the foils contact each other forming very acute angles, and theends of the contact lines are exposed at both end faces of the honeycombbody. When a liquid, having good wettability with a metal foil and lowviscosity, comes in contact with a honeycomb body at one or both endfaces, it is sucked up along the contact lines of the flat andcorrugated foils by the capillary phenomenon. Japanese Patent No.2548796 discloses a method of brazing a honeycomb body characterized bysucking up a liquid adhesive along the contact lines of the flat andcorrugated foils taking advantage of the capillary phenomenon by makingthe honeycomb body contact the surface of the liquid adhesive at one orboth of the axial end faces, and then supplying a brazing filler metalin powder to have it deposited at the portions of the contact linesalong which the adhesive has been sucked up. By this method, theadhesive is sucked up only along the contact lines of the flat andcorrugated foils, it is not deposited at any other areas and, for thisreason, the consumption of the brazing filler metal is controlled to theleast and the problems such as corrosion by the brazing filler metal areavoided.

U.S. Pat. No. 5,082,167 discloses a method of sucking up an adhesivealong the contact lines over the full axial length of the honeycomb bodyat outer layers by placing the honeycomb body on an annular basematerial holding the adhesive and, after that, of sucking up theadhesive to only one or both end portions of the honeycomb body byplacing it on a cylindrical base material holding the adhesive andhaving an outer diameter equal to the inner diameter of the annular basematerial. According to this method, it is possible to braze the foilsover the full axial length of the honeycomb body at outer layers andonly at one or both end portions of the honeycomb body at inner layersby selecting the method of sucking up the adhesive.

A honeycomb body having a high structural reliability to withstand thethermal load and stress imposed on the catalyst support and being notbroken in the event of an engine misfire can be manufactured by bondingthe flat and corrugated foils over the full axial length of thehoneycomb body at outer layers and also at an end of the honeycomb bodyat inner layers and/or a portion over a cross section of the honeycombbody at inner layers.

Another method of applying an adhesive to the wave tops of a corrugatedfoil before winding the flat and corrugated foils into a honeycomb bodyand then, after the winding, feed a brazing filler metal to thehoneycomb body to have it deposited in the honeycomb body is alsopracticed. According to the method, the adhesive is applied to the wavetops of the corrugated foil by placing a pair of parallel rolls coatedwith the adhesive on their surfaces with a gap between them and makingthe corrugated foil pass through the gap and contact the roll surfacesonly at the wave tops. By this method, however, if the gap between theparallel rolls is only a little too large, some of the wave tops of thecorrugated foil may fail to come in contact with the surface of eitherof the rolls, causing the failure of the brazing and the consequentdeterioration of structural strength and reliability as a result of nobrazing at such portions. If the gap is only a little too narrow, on theother hand, the adhesive is applied to the wave tops of the corrugatedfoil over excessively large areas and the brazing filler metal in powderis deposited at all the areas covered with the adhesive. For thisreason, the consumption of the filler metal becomes large and the metalfoils constituting the honeycomb body are alloyed over a large area withthe metal contained in the brazing filler material. This is undesirablesince the alloying deteriorates mechanical properties of the foil.

A corrugated foil used for a honeycomb body is manufactured by applyingplastic corrugation work to a flat foil. As a result of the plasticwork, the surface of the corrugated foil may bend: for example, the wavetops may bend in the direction of foil width. In case of employing theabove-mentioned method of applying the adhesive to the wave tops of acorrugated foil at the bonding portion over the full axial length of thehoneycomb body outer layers using a pair of parallel rolls, if theadhesive is applied to such bent corrugated foil, the adhesiveapplication on the concave side of the bending of the corrugated foilwill be insufficient in the width center portion of the foil and toomuch at both the edges of the foil. On the convex side of the bending ofthe corrugated foil, on the contrary, the adhesive application will betoo much at the width center portion of the foil and too little at boththe edges.

Since an adhesive has to be applied to the foil over the full axiallength of the honeycomb body at outer layer, it is necessary to prepareadhesive applicator rolls for this purpose. Further, since the adhesivehas to be applied to one or both ends of the honeycomb body at innerlayer and/or to a portion over a cross section of the honeycomb bodyinner layers, it is necessary to prepare another adhesive applicatorrolls for these purposes. As a consequence, as long as a method ofapplying the adhesive using the applicator rolls is employed, pluralsets of the applicator rolls are required and this has been a reason whythe equipment cost of honeycomb body manufacturing facilities are high.

By the method of sucking up the adhesive from one or both ends of ahoneycomb body, however, it has been impossible to apply the adhesiveselectively to a bonding portion over a cross section of the honeycombbody inner layers. Therefore, it has been impossible to employ themethod of sucking up an adhesive for manufacturing a honeycomb bodyconforming to the countermeasure against an engine misfire.

DISCLOSURE OF THE INVENTION

The object of the present invention is to provide a method ofmanufacturing a honeycomb body, free from the insufficient or excessiveapplication of an adhesive which is seen in the cases of adhesiveapplication methods using rolls, capable of reducing the equipment costof facilities for manufacturing honeycomb body and conforming to thecountermeasure against an engine misfire problem of the honeycomb body,in a method of manufacturing a honeycomb body wherein a flat metal foiland a corrugated metal foil are wound in layers, one over the other, andbrazed at the outermost layer or more of the honeycomb body over thefull axial length and at one or both ends of the honeycomb body and/orat another portion inside the honeycomb body over a cross section whichis located away from one or both ends thereof in the axial direction.

The gist of the present invention, therefore, is as follows:

(1) A method of manufacturing a honeycomb body 1 formed by winding aflat metal foil 3 and a corrugated metal foil 4 in layers and brazingthem at the bonding portion 16 over the full axial length of thehoneycomb body outer layers, at a bonding portion 17 which is located atone or both ends of the honeycomb body, and/or at a bonding portion 18inside the honeycomb body over a cross section which is located awayfrom one or both ends thereof in the axial direction, characterized by:

-   -   (a) applying an adhesive 26 to the portions to be brazed of the        flat or corrugated foil corresponding to the bonding portion 17        which is located at one or both ends of the honeycomb body        and/or the bonding portion 18 inside the honeycomb body over a        cross sect on which is located away from one or both ends        thereof in the axial direction;    -   (b) then, winding the flat and corrugated foils in layers to        form a honeycomb body;    -   (c) then, depositing a liquid adhesive 33 at the portion of the        honeycomb body corresponding to the bonding portion 16 over the        full axial length of the honeycomb body outer layers by making        the portion of one or both end faces of the honeycomb body        corresponding to the bonding portion 16 over the full axial        length of the honeycomb body outer layers contact the surface of        the liquid adhesive 33 and having the adhesive 33 sucked up        along contact lines 5 of the flat and corrugated foils; and    -   d) then, feeding a brazing filler metal in powder to the        honeycomb body so as to have it deposited at the portions where        the adhesives (26 and 33) have been applied or deposited.

(2) A method of manufacturing a honeycomb body according to the item(1), characterized in that the bonding portion 16 over the full axiallength of the honeycomb body outer layers covers ⅓ or less of the radiusof the honeycomb body from its outermost layer toward the centerthereof.

(3) A method of manufacturing a honeycomb body according to the item (1)or (2), characterized in that the portions of the flat foil 3 or thecorrugated foil 4 to which the adhesive 26 is applied are the portionscorresponding to the wave tops 6 of the corrugated foil 4.

(4) A method of manufacturing a honeycomb body according to any one ofthe items (1) to (3), characterized by applying the adhesive 26 to theportions of the flat foil 3 or the corrugated foil 4 by making rollscovered with the adhesive 26 on the surfaces contact the flat orcorrugated foil.

(5) A method of manufacturing a honeycomb body according to any one ofthe items (1) to (4), characterized by depositing the liquid adhesive 33at the portion of the honeycomb body corresponding to the bondingportion 16 over the full axial length of the honeycomb body outer layersby making a porous body 31 impregnated with the liquid adhesive 33contact the portion of one or both end faces of the honeycomb bodycorresponding to the bonding portion 16 over the full axial length ofthe honeycomb body outer layers and, thus, having the adhesive 33 suckedup along the contact lines 5 of the flat and corrugated foils.

(6) A method of manufacturing a honeycomb body according to the item(5), characterized in that the porous body 31 has an annular shape.

(7) A method of manufacturing a honeycomb body according to any one ofthe items (1) to (6), characterized in that the viscosity of the liquidadhesive 33 to be sucked up to the honeycomb body is lower than that ofthe adhesive 26 to be applied by rolls.

(8) A method of manufacturing a honeycomb body formed by winding a flatmetal foil 3 and a corrugated metal foil 4 in layers and brazing them atthe bonding portion 20 over the full axial length of the honeycomb bodyouter layers, at a bonding portion 17 which is located at one or bothends of the honeycomb body, and/or at a bonding portion 18 inside thehoneycomb body over a cross section which is located away from one orboth ends thereof in the axial direction, characterized by:

-   -   (a) applying an adhesive 26 to the portions to be brazed of the        flat or corrugated foil corresponding to the bonding portion 18        inside the honeycomb body over a cross section which is located        away from one or both ends thereof in the axial direction and to        the portion 20 a excluding the portion which is located at the        gas inlet end of the honeycomb body from the bonding portion 20        over the full axial length of the honeycomb body outer layers;    -   (b) then, winding the flat foil 3 and the corrugated foil 4 in        layers to form a honeycomb body;    -   (c) then, depositing a liquid adhesive 33 at the portion 20 b        which is located at the gas inlet end out of the bonding portion        over the full axial length of the honeycomb body outer layers        and the bonding portion 17 which is located at one or both ends        of the honeycomb body, by making the gas inlet end face 9 of the        honeycomb body adhere to the surface of the liquid adhesive 33        and having the adhesive 33 sucked up along contact lines 5 of        the flat and corrugated foils; and    -   (d) then, feeding a brazing filler metal in powder to the        honeycomb body so as to have it deposited at the portions where        the adhesives (26 and 33) have been applied or deposited.

(9) A method of manufacturing a honeycomb body according to the item(8), characterized in that the bonding portion 20 over the full axiallength of the honeycomb body outer layers covers ⅓ or less of the radiusof the honeycomb body from its outermost layer toward the center.

(10) A method of manufacturing a honeycomb body according to the item(8) or (9), characterized in that the portions of the flat foil 3 or thecorrugated foil 4 to which the adhesive 26 is applied are the portionscorresponding to the wave tops 6 of the corrugated foil 4.

(11) A method of manufacturing a honeycomb body according to any one ofthe items (8) to (10), characterized by applying the adhesive 26 to theportions of the flat foil 3 or the corrugated foil 4 by making rollscovered with the adhesive 26 on the surface contact the flat orcorrugated foil.

(12) A method of manufacturing a honeycomb body according to any one ofthe items (8) to (11), characterized in that the viscosity of the liquidadhesive 33 to be sucked up to the honeycomb body is lower than that ofthe adhesive 26 to be applied by rolls.

(13) A method of manufacturing a honeycomb body according to any one ofthe items (1) to (12), characterized in that the flat foil 3 hascorrugation 14 and the wave height of the corrugation 14 is smaller thanthe wave height of the corrugated foil 4.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view partly in section of a honeycomb bodyaccording to the present invention encased in a cylindrical metaljacket.

FIGS. 2(a), 2(b), 2(c) and 2(d) are sectional views of honeycomb bodiesaccording to the present invention.

FIG. 3 is a side elevation view showing a manner of applying an adhesiveto a flat foil using rolls according to the present invention.

FIG. 4 is a side elevation view showing a manner of applying an adhesiveto a corrugated foil using rolls according to the present invention.

FIG. 5 is a perspective view showing a manner of applying an adhesive toa corrugated foil using rolls according to the present invention.

FIG. 6 is a perspective view showing a manner of winding flat andcorrugated foils in layers to form a honeycomb body.

FIG. 7 is a sectional view showing the situation how an adhesive isdeposited along the contact lines of flat and corrugated foils.

FIGS. 8(a) and 8(b) are illustrations showing a manner of having anadhesive sucked up to a honeycomb body.

FIGS. 9(a) and 9(b) are illustrations showing a manner of having anadhesive sucked up to a honeycomb body.

FIGS. 10(a) and 10(b) are illustrations showing a manner of having anadhesive sucked up to a honeycomb body.

FIGS. 11(a) and 11(b) are illustrations showing a manner of having anadhesive sucked up to a honeycomb body.

FIGS. 12(a) and 12(b) are illustrations showing a manner of having anadhesive sucked up to a honeycomb body.

FIG. 13 comprises illustrations showing a manner of having an adhesivesucked up to a honeycomb body: FIG. 13(a) shows the status before anadhesive is sucked up, and FIG. 13(b) the status after an adhesive issucked up.

FIG. 14 comprises illustrations showing a manner of having an adhesivesucked up to a honeycomb body: FIG. 14(a) shows the status before anadhesive is sucked up, and FIG. 14(b) the status after an adhesive issucked up.

FIG. 15 comprises partial sectional views of honeycomb bodies in thecases that flat foils are corrugated: FIG. 15(a) shows a case that thewavelength of the corrugation of a flat foil is smaller than the same ofa corrugated foil; and FIG. 15(b) a case that the former is larger thanthe latter.

BEST MODE FOR CARRYING OUT THE INVENTION

The subject of the present invention is a honeycomb body 1 formed bywinding a flat metal foil 3 and a corrugated metal foil 4 in layers, oneover the other, and brazing them. The honeycomb body 1 includes ahoneycomb body of a cylindrical shape formed by winding a flat foil 3and a corrugated foil 4 in layers around a shaft, and another having asectional shape in the form of a racetrack formed by winding a flat foiland a corrugated foil in layers leaving a hollow shaft at the center andthen closing the hollow shaft by pressing.

The reason why the flat foil 3 and the corrugated foil 4 are wound inlayers is that a cell formed between the flat foil and the corrugatedfoil in one wavelength by winding the foils in layers is used as a pathof emission gas from a automobile engine. Since the purpose of thewinding is to form the cells, it is not imperative that the flat foil 3should be dead flat and, for this reason, as described in the item (13)of the present invention, a foil having corrugation 14 can, of course,be used also as the flat foil 3 according to the present invention.

The brazed portions of the flat foil 3 and the corrugated foil 4 of thehoneycomb body 1 are as follows: in the outer layers of the honeycombbody, the foils are bonded at the bonding portion 16 over the full axiallength of the honeycomb body outer layers 12 covering the outermostlayer of the foils or more; and in the inner layers 13 of the honeycombbody, that is the layers excluding the outer layers 12 (the layers wherethe foils are bonded over the full axial length), they are bonded at abonding portion or bonding portions 17 at either of the ends (the gasinlet end, the gas outlet end or both ends) of the honeycomb body and/ora bonding portion 18 inside the honeycomb body over a cross sectionwhich is located away from one or both ends thereof in the axialdirection. FIG. 2(a) shows a case that the foils are bonded at thebonding portion 16 over the full axial length of the honeycomb bodyouter layers and a bonding portion 17 which is located at the gas inletend of the honeycomb body; FIG. 2(b) a case that the foils are bonded atthe bonding portion 16 over the full axial length of the honeycomb bodyouter layers and a bonding portion 18 inside the honeycomb body over across section; FIG. 2(c) a case that they are bonded at the bondingportion 16 over the full axial length of the honeycomb body outerlayers, a bonding portion 17 which is located at the gas inlet end ofthe honeycomb body and a bonding portion 18 inside the honeycomb bodyover a cross section; and FIG. 2(d) a case that they are bonded at thebonding portion 16 over the full axial length of the honeycomb bodyouter layers, a bonding portion 17 which is located at the gas inlet endof the honeycomb body and the other bonding portion 17 which is locatedat the gas outlet end.

In the outer layers 12 of the honeycomb body, the foils are bonded overthe full axial length of the honeycomb body in order that the honeycombbody may withstand the large thermal stress imposed on the portion nearits outer surface, and thus prevents its fracture. In the inner layers13 (the layers excluding the outer layers 12) of the honeycomb body, thefoils are bonded in an entire cross section at one or both ends of thehoneycomb body and/or in a cross section inside it away from one or bothends in the axial direction. Since the honeycomb body is bonded in theinner layers 13 only at a part of the axial length, the thermal stressgenerated inside the honeycomb body can be reduced. When the honeycombbody has a bonding portion at the gas inlet end, the problem of bondedportions of the honeycomb body being broken apart in the event of anengine misfire can be prevented by bonding the foils over a crosssection inside the honeycomb body or at the gas outlet end, in additionto the gas inlet end.

It is preferable that the bonding portion 16 over the full axial lengthof the honeycomb body outer layers covers ⅓ or loss of the radius of thehoneycomb body from its outermost layer toward the center as describedin the item (2). If the radial thickness of the bonded portion over thefull axial length exceeds ⅓ of the 3D radius starting from the outersurface, it becomes impossible to sufficiently relax the thermal stressgenerated in the inner layers.

For the brazing of the bonding portion(s) 17 at the end(s) (the gasinlet end, the gas outlet end or both ends) of the honeycomb body andthe bonding portion 18 inside the honeycomb body over a cross sectionwhich is located away from one or both ends thereof in the axialdirection, the adhesive 26 is applied to the areas to be brazed ofeither of the flat foil 3 and the corrugated foil 4, prior to windingthem in layers. FIG. 3 shows a case of applying an adhesive 26 to a flatfoil 3, and FIGS. 4 and 5 a case of applying an adhesive 26 to the wavetops 6 of a corrugated foil 4. In the case that the adhesive 26 isapplied to a flat foil 3, however, the adhesive 26 may be applied to theareas not to be contacted with the corrugated foil, and to be coatedlater with the catalytic materials. These areas will then be coveredwith the brazing filler metal in powder and, as a consequence, anexcessive amount of the brazing filler metal will be consumed. Besides,the foil material of the flat foil may be alloyed at the areas coveredwith the brazing filler metal by the elements contained in it, adverselyaffecting mechanical properties of the flat foil 3. On the other hand,in the case that the adhesive 26 is applied to the wave tops 6 of acorrugated foil 4 as described in the item (3) of the present invention,the adhesive 26 is applied to the corrugated foil only on the contactlines 5 with the flat foil and the brazing filler metal is depositedonly on the contact lines 5 of the flat and corrugated foils, which ismore preferable than the above case.

When applying the adhesive 26 to the surfaces of a flat foil 3 or acorrugated foil 4, it is preferable to do that by making rolls coveredwith the adhesive 26 on the surface contact the flat or corrugated foilas described in the item (4). An example of the application of theadhesive 26 to the wave tops 6 of a corrugated foil 4 is explainedhereafter based on FIG. 4. A pair of adhesive applicator rolls (21 a and21 b) is arranged in parallel to each other with a gap between them andthe corrugated foil 4 is made to pass through the gap. An adhesive tank22 is provided for each of the applicator rolls 21. In the example shownin FIG. 4, pairs of second rolls 23 and third rolls 24 are equippedbetween the adhesive tanks 22 and the adhesive applicator rolls 21, andthese rolls rotate as the applicator rolls 21 do. The third rolls 24 arepartially immersed in the adhesive 26 in the adhesive tanks 22 and theadhesive 26 covers the surfaces of the third rolls as they rotate. Theadhesive 26 on the surfaces of the third rolls is transferred onto thesurfaces of the second rolls as they rotate, and then the adhesive 26 onthe surfaces of the second rolls is transferred onto the surfaces of theadhesive applicator rolls, to be finally transferred from the surfacesof the adhesive applicator rolls onto the wave tops 6 of the corrugatedfoil passing between them. The second rolls 23 and the third rolls 24can be omitted as the case may be. The pairs of the adhesive applicatorrolls, second rolls, third rolls, confronting each other, and adhesivetanks constitute an adhesive application apparatus 25.

Explained hereinafter, based on FIG. 5, is a case of applying anadhesive 26 to the wave tops 6 corresponding to two bonding portions,namely the bonding portion 17 at the gas inlet end of the honeycomb bodyand the bonding portion 18 inside the honeycomb body over a crosssection which is located away from one or both ends thereof in the axialdirection. A pair of adhesive applicator rolls (21 a and 21 b) and theaccompanying adhesive application apparatus are provided for applyingthe adhesive 26 to the width edge portions 27 of a corrugated foilcorresponding to the bonding portion 17 at the end of the honeycombbody. Another pair of adhesive applicator rolls (21 c and 21 d) and theaccompanying adhesive application apparatus are provided for applyingthe adhesive 26 to the inner portions 28 of the corrugated foil which islocated away from the edges corresponding to the bonding portion 18inside the honeycomb body over a cross section. Note that FIG. 5 doesnot show the rolls 21 a and 21 d.

After the application of the adhesive 26 to the flat foil 3 or thecorrugated foil 4, the flat foil 3 and the corrugated foil 4 are woundin layers, as shown in FIG. 6, to form the honeycomb body 1. Thehoneycomb body 1 may be encased in the cylindrical metal jacket 2 atthis stage.

The method of sucking up the adhesive 33 is employed for the bondingportion 16 over the full axial length of the honeycomb body outerlayers. The honeycomb body 1 formed by winding the flat and corrugatedfoils is placed to come in contact with the surface of the liquidadhesive 33 at a part of one of its end faces. The part of the honeycombbody to contact the surface of the liquid adhesive 33 is the part of oneof its end faces corresponding to the bonding portion 16 over the fullaxial length of the honeycomb body outer layers. Since the ends of thecontact lines 5 of the flat and corrugated foils are exposed at the endfaces of the honeycomb body, the adhesive 33 contacts the contact lines.Owing to the very acute angles at which the flat and corrugated foilscontact each other, the adhesive 33 is sucked up along the contact lines5 from the end in contact with the liquid adhesive 33 over the fullaxial length of the honeycomb body to the other end by the capillaryphenomenon. Thus the adhesive 33 is deposited all along the contactlines 5 of the flat foil 3 and the corrugated foil 4 of the honeycombbody as shown in FIG. 7.

By the method of sucking up the adhesive 33 described above employed forthe bonding portion 16 over the full axial length of the honeycomb bodyouter layers, different from the conventional method of applying theadhesive to the wave tops of the corrugated foil using a pair ofparallel rolls, the adhesive is deposited evenly along the contact linesand, consequently, the consumption of the brazing filler metal isreduced and the alloyed parts of the foils forming the honeycomb bodyare minimized. Further, even when the surface of the corrugated foil isbent before it is wound, the flat and corrugated foils contact eachother tightly by elastic deformation of the foils once they are wound toform a honeycomb body, and, for this reason, the adhesive is evenlydeposited along every contact line by the method of sucking up theadhesive according to the present invention, eliminating inappropriateadhesive application as seen in the cases of the adhesive applicationmethods using the rolls.

The contact of the honeycomb body with the liquid adhesive 33 at one orboth end faces has to be limited to the outer layers 12 of the honeycombbody where the flat and corrugated foils have to be bonded all throughthe axial length of the honeycomb body. According to the item (5) of thepresent invention, it is possible to deposit the adhesive 33 at thecontact lines of the flat and corrugated foils by sucking it up alongthe contact lines by impregnating a porous body 31 with the adhesive 33and making it contact the area of one or both end faces of the honeycombbody corresponding to the portion to be bonded over the full axiallength of the honeycomb body. An elastic porous body such as a sponge ora cavernous body, a metal porous body, a ceramic porous body, etc. canbe used as the porous body 31.

The adhesive can be deposited as described above, specifically, byforming the porous body 31 in a ring shape as shown in FIG. 8(b) andmaking the inner diameter of the ring equal to the diameter of theinnermost layer of the bonding portion 16 of the outer layers of thehoneycomb body, as described in the item (6). The outer diameter of thering is set equal to or larger than the outer diameter of the honeycombbody 1. The ring-shaped porous body 31 is impregnated with the adhesive33 by placing it in an adhesive tank 32. The honeycomb body 1 contactsthe liquid adhesive 33 at one or both end faces by making it contact theporous body 31 coaxially as shown in FIG. 8(a). When the honeycomb body1 has a sectional shape in the form of a racetrack, the porous body 31is preferable to be of the racetrack shape accordingly.

The porous body 31 may also be of a disc shape with a shield plate 34placed on it as illustrated in FIG. 9. The outer diameter of the shieldplate 34 is preferable to be equal to the diameter of the innermostlayer of the bonding portion 16 of the outer layers of the honeycombbody. The honeycomb body 1 is placed on the porous body 31 coaxiallywith the shield plate 34. Since it will be only at the area outside theshield plate 34 that one or both end faces of the honeycomb body 1contacts the porous body 31 by the above arrangement, only the area ofone or both end faces of the honeycomb body corresponding to the bondingportion 16 over the full axial length of the honeycomb body outer layerswill contact the liquid adhesive 33 permeating through the porous body.

When the shield plate is used, it is preferable to use an elastic porousbody comprising of sponge, cavernous material or the like as the porousbody 31 for realizing a good contact with the honeycomb body.

After applying the adhesives 26 and depositing the adhesives 33 at theportions of the honeycomb body to be brazed as explained above, thehoneycomb body is fed with the brazing filler metal in powder, which isdeposited only at the areas covered with the adhesives 26 and 33. Thebrazing filler metal in powder not caught by the adhesives is dischargedfrom the honeycomb body.

The honeycomb body 1 may be encased in the cylindrical metal jacket 2 atany of the following stages: upon winding the flat and corrugated foilsin layers into a honeycomb body, upon sucking up the adhesive 33 to thebonding portion, or upon depositing the brazing filler metal in powder.

The outer surface of the honeycomb body 1 is bonded to the inner surfaceof the cylindrical metal jacket 2 usually by attaching a foil of abrazing filler metal or depositing a brazing filler metal in powder.When the outermost foil of the honeycomb body 1 is the corrugated foil,the adhesive 33 may be deposited along the contact lines of the wavetops of the corrugated foil and the inner surface of the cylindricalmetal jacket 2 by the method of sucking up the adhesive after insertingthe honeycomb body 1 into the metal jacket 2.

Then, bonding of the honeycomb body is completed by brazing the bondingportions by charging the honeycomb body encased in the cylindrical metaljacket into a high temperature furnace to heat it and melting thebrazing filler metal in powder deposited along the contact lines of theflat and corrugated foils.

A solution, for example, of polyvinyl alcohol is used as the liquidadhesive 33 in the method of sucking up the adhesive 33 according to thepresent invention. The better the wettability of the adhesive 33 withthe surfaces of the metal foils, the better the sucking-up proceeds. Thesurface tension of the adhesive 33 can be controlled by adding a surfaceactive agent to it as the case may be, and it is thus possible tocontrol the condition to suck up the adhesive along the contact lines ofthe flat and corrugated foils. It has to be noted that the viscosity ofthe liquid adhesive 33 has to be within a suitable range lower than aprescribed value, because the adhesive 33 will not be sucked up smoothlyif its viscosity is too high.

Polyvinyl alcohol or high molecular polymers, for example, may be usedas the adhesive 26 to be applied partly to the edge portions or theportions away from the edges of the metal foil according to the presentinvention. If the adhesive 26 has too low a viscosity, it will spread bysurface tension between the contact surfaces of the flat and corrugatedfoils when they are wound in layers. For this reason the adhesive 26 hasto have a viscosity within a suitable range above a prescribed value.

In the present invention, the sucking-up of the liquid adhesive 33 iskept smooth and the adhesive 26 is prevented from spreading too much bymaking the viscosity of the liquid adhesive 33 lower than that of theadhesive 26 as described in the item (7).

When the adhesive 26 is applied to the flat or corrugated foil, if theadhesive 26 is applied also to the areas to be included in the bondingportion 16 over the full axial length of the honeycomb body outerlayers, and if the adhesive 33 is sucked up thereafter, the adhesive 33cannot be sucked up beyond the portions where the adhesive 26 hasalready been applied. When applying the adhesive 26, therefore, it isnecessary not to apply it to the areas to be included in the bondingportion 16 over the full axial length of the honeycomb body outerlayers.

FIG. 8 shows an example of a method of manufacturing a honeycomb bodyhaving the bonding portion 16 over the full axial length of thehoneycomb body in its outer layers and the bonding portion 17 which islocated at the gas inlet end of the honeycomb body, and FIG. 9 anotherto manufacture a honeycomb body having the bonding portion 16 over thefull axial length of the honeycomb body outer layers, the bondingportion 17 which is located at the gas inlet end of the honeycomb bodyand a bonding portion 18 inside the honeycomb body over a cross section.In both the cases as shown in FIGS. 8 and 9, the adhesive 26 is appliedto the areas of the foil corresponding to the bonding portion 17 whichis located at the gas inlet end of the honeycomb body and the bondingportion 1B inside the honeycomb body over a cross section before windingthe flat and corrugated foils, and the adhesive 33 is deposited at thebonding portion 16 over the full axial length of the honeycomb body bythe method of sucking up the adhesive 33 after forming the flat andcorrugated foils into a honeycomb body.

It is also possible, however, to deposit the adhesive 33 at the bondingportion 17 which is located at one or both ends of the honeycomb body bythe method of sucking up the adhesive 33. In the example shown in FIG.10, the adhesive 26 is applied to the bonding portion 18 inside thehoneycomb body over a cross section before winding the flat andcorrugated foils and, besides, suck-up inhibitor coated zones 35 areprovided on the surface of the flat foil 3 by applying an agent toprevent the sucking-up of the adhesive such as fat, grease, oil, etc.also before winding the foils. When the agent to prevent the sucking-upof the adhesive is applied to the flat foil 3, the adhesive 33 is notsucked up beyond the suck-up inhibitor coated zone 35 owing to poorwettability of the suck-up inhibitor coated zone 35 with the adhesive33. When the whole gas inlet end face 9 of the honeycomb body 1 is madeto contact the porous body 31 as shown in FIG. 10(a) after the aboveprocessing, the adhesive 33 is sucked up along the contact lines of theflat and corrugated foils in the whole section of the honeycomb body.Whereas, in the bonding portion 16 over the full axial length of thehoneycomb body outer layers, the adhesive 33 is sucked up over the fullaxial length because no suck-up inhibitor coated zone 35 is provided inthe bonding portion 16, the adhesive 33 is sucked up only within the endportion 17 of the honeycomb body in the inner layers 13 owing to theexistence of the suck-up inhibitor coated zone 35. It is also possibleto deposit the adhesive 33 in the bonding portions 17 at both the endsof the honeycomb body 1, by turning it upside down after the above stepso as to make the gas outlet end face 10 contact the porous body at theinner layers as shown in FIG. 10(b).

The suck-up inhibitor coated zone 35, according to the presentinvention, is provided, in the axial direction, at the inside of, andcontiguous to a portion to be formed as the bonding portion 17 which islocated at one or both ends of honeycomb body.

As shown in FIG. 10(a) and FIG. 10(b), for example, the suck-upinhibitor coated zones 35 are provided, in the axial direction, at theinside of, and contiguous to a portion to be formed as the bondingportion 17 which is located at the gas inlet end of honeycomb body andat the inside of, and contiguous to a portion to be formed as thebonding portion 17 which is located at the gas outlet end of honeycombbody.

As shown in FIGS. 11, 13 and 14, explained hereinafter, the suck-upinhibitor coated zone 35 is provided, in the axial direction, at theinside of, and contiguous to a portion to be formed as the bondingportion 17 which is located at the gas inlet end of honeycomb body.

The suck-up inhibitor is coated on the surface of the flat foil 3 in theabove examples, however, it can be coated on the surface of thecorrugated foil 4 or both foils.

The following sequence of procedures as shown in FIG. 11 is also viable:to apply the adhesive 26 to the areas of the corrugated foilcorresponding to the bonding portion 18 inside the honeycomb body over across section and apply the fat, grease, oil, etc. to the areas of theflat foil corresponding to the suck-up inhibitor coated zone 35; to windthe flat and corrugated foils into a honeycomb body thereafter; to makeone or both end faces of the honeycomb body contact the porous body 31at the outer layers as shown in FIG. 11(a) to have the adhesive 33deposited along the bonding portion 16 over the full axial length of thehoneycomb body outer layers by the method of sucking up the adhesive 33;and subsequently to make the end face of the honeycomb body contact theporous body 31 at the inner layers as shown in FIG. 11(b) to have theadhesive 33 deposited at the bonding portion 17 at the end of thehoneycomb body also by the method of sucking up the adhesive 33.

The axial core 7 of the honeycomb body 1, where the winding of the flatfoil 3 and the corrugated foil 4 is initiated, sometimes becomes weakerthan the other part of the honeycomb body. For this reason, it ispreferable to form a bonding portion at the axial core 7 all along theaxial length of the honeycomb body as shown in FIG. 12. The adhesive 33can be sucked up along both the bonding portion 17 in the outer layersand the bonding portion at the axial core 7 at the same time, as shownin FIG. 12(a), by using an annular porous body 31 a and a columnarporous body 31 b as a porous body as shown in FIG. 12(b).

The present invention is explained hereafter in relation to the item (8)based on FIGS. 13 and 14.

If the adhesive 33 is to be deposited all along the axial length of ahoneycomb body 1 having a long axial length by the method of sucking upthe adhesive, there may occur a problem that too much of the adhesive 33is deposited near the end face of the honeycomb body contacting thesurface of the liquid adhesive 33 or insufficient adhesive reaches theend of the honeycomb body opposite the end contacting the surface of theliquid adhesive 33. If sound bonding lines are formed by the method ofsucking up the adhesive 33 in a part (the gas inlet end portion 20 b) ofthe axial length of the honeycomb body, a sufficiently strong bondingportion can be formed in the bonding portion 20 all along the axiallength in the outer layers, even when the method of applying theadhesive 26 has been employed before winding the flat and corrugatedfoils for the rest (the portion 20 a excluding the gas inlet end portion20 b) of the axial length.

With regard to the bonding portion 17 at the gas inlet end of thehoneycomb body, on the other hand, for avoiding insufficient or unevenapplication of the adhesive, it is preferable to employ the method ofsucking up the adhesive 33 rather than the method of applying theadhesive 26 before winding the flat and corrugated foils, because thebonding portion 17 is meant to secure the strength of the inner layersof the honeycomb body.

FIG. 13(a) shows the condition before the adhesive 33 is sucked up.Here, before winding the flat foil 3 and the corrugated foil 4 inlayers, the adhesive 26 has been applied to the areas corresponding tothe bonding portion 18 inside the honeycomb body over a cross sectionand the portion 20 a excluding the portion which is located at the gasinlet end of the honeycomb body from the bonding portion over the fullaxial length of the honeycomb body outer layers. A suck-up inhibitorcoated zone 35 has also been provided near the gas inlet end face 9 ofthe honeycomb body by applying fat, grease, oil, etc. to the flat foil.Then, the adhesive 33 is deposited along the contact lines 5 of the flatand corrugated foils by making the whole gas inlet end face 9 contactthe surface of the liquid adhesive 33 to suck it up as shown in FIG.13(b). The adhesive 33 is sucked up into the gas inlet side portion 20 bof the bonding portion over the full axial length of the honeycomb bodyouter layers up to the lower end of the portion where the adhesive 26has been applied and, in the inner layers of the honeycomb body, up tothe lower end of the suck-up inhibitor coated zone 35, achieving thecondition shown in FIG. 13(b).

The axial length of the gas inlet side portion 20 b of the bondingportion over the full axial length of the honeycomb body outer layerscan be made longer than the axial length of the bonding portion 17 atthe end of the honeycomb body as shown in FIG. 14. By doing so, thebonding portion 20 over the full axial length of the honeycomb bodyouter layers can be made more sound than in the case shown in FIG. 13.

The inventions according to the items (9) to (12) are applications ofthe inventions according to the items (2) to (4) and (7) to theinvention according to the item (6), and the inventions according to theitems (9) to (12) realize the same effects of the inventions accordingthe items (2) to (4) and (7) more efficiently.

As explained before, the reason why the flat foil 3 and the corrugatedfoil 4 are wound in layers, one over the other, in the present inventionis that a cell formed between the corrugated foil in one wavelength andthe flat foil by winding the foils in layers is used as a path of theemission gas from a automobile engine. Since the purpose of the windingis to form the cells, it is not imperative that the flat foil 3 shouldbe dead flat as far as the purpose is attained. According to the item(13) of the present invention, the flat foil 3 has corrugation 14 asshown in FIG. 15. Here, the wavelength of the corrugation 14 of the flatfoil 3 is shorter than that of the corrugated foil 4 and the wave heightof the corrugation 14 of the flat foil 3 is also smaller than that ofthe corrugated foil 4. As a result, the formation of the cells, or thepaths of the emission gas, by winding the flat foil 3 and corrugatedfoil 4 in layers is not different from the case of winding a flat toilhaving no corrugation with a corrugated foil. The wavelength of thecorrugation 14 of the flat foil 3 may either be shorter than that of thecorrugated foil 4 as shown in FIG. 15(a) or longer than the same asshown in FIG. 15(b). It is preferable for forming a honeycomb bodyhaving good cell shapes that the wavelength of the corrugation 14 of theflat foil 3 is 85% or less of the same of the corrugated foil 4 and thatthe wave height of the corrugation 14 of the flat foil 3 is 50% or lessof the same of the corrugated foil 4. The use of a flat foil 3 havingthe corrugation 14 specified above increases elasticity of the flat foil3 and improves the service life of the honeycomb body.

INDUSTRIAL APPLICABILITY

A honeycomb body for metal catalyst support use manufactured by a methodaccording to the present invention has high structural reliabilityagainst thermal load and stress imposed on a catalyst support andresistance against the fracture problem caused by a misfire of aautomobile engine, as a result of bonding the foils over the full axiallength of the honeycomb body outer layers and at one or both ends of thehoneycomb body inner layers and/or at another portion of the honeycombbody inner layers which is located inside the honeycomb body over across section.

The present invention eliminates poor bonding and excessive consumptionof the brazing filler metal and realizes excellent bonding of the foils,compared with the methods to apply the adhesive 26 to a flat orcorrugated foil using rolls, because the adhesive is deposited by amethod of sucking it up after the flat and corrugated foils are wound inlayers; at the bonding portion 16 over the full axial length of thehoneycomb body outer layers according to the items (1) to (7) of thepresent invention and at the bonding portion 17 which is located at thegas inlet end of the honeycomb body according to the item (8) of thepresent invention. By the present invention, it is possible to evenlydeposit the adhesive along the contact lines of the foils and evenlybraze the bonding portion over the full axial length even when thecorrugated foil is bent in its width direction.

By the present invention, the equipment cost of the honeycomb bodymanufacturing facilities can be lowered, because the application of anadhesive by rolls can be limited only to the bonding portion at one orboth ends of the honeycomb body and/or the bonding portion inside thehoneycomb body over a cross section which is located away from one orboth ends thereof in the axial direction.

Since the present invention employs also a method of applying theadhesive by rolls, it is possible to apply the adhesive selectively tothe areas of a foil corresponding to a bonding portion inside ahoneycomb body over a cross section and, therefore, it is possible tomanufacture a honeycomb body conforming to the countermeasure against anengine misfire problem.

1. A method of manufacturing a honeycomb body formed by winding a flatmetal foil and a corrugated metal foil in layers and brazing them at thebonding portion over the full axial length of the honeycomb body outerlayers, at a bonding portion which is located at one or both ends of thehoneycomb body, and/or at a bonding portion inside the honeycomb bodyover a cross section which is located away from one or both ends thereofin the axial direction, characterized by: (a) prior to winding the flatand corrugated foils in layers to form the honeycomb body, applying anadhesive to the portions to be brazed of the flat or corrugated foilcorresponding to the bonding portion which is located at one or bothends of the honeycomb body and/or the bonding portion inside thehoneycomb body over a cross section which is located away from one orboth ends thereof in the axial direction; (b) then, winding the flat andcorrugated foils in layers to form the honeycomb body; (c) then, afterwinding the flat and corrugated foils in layers to form the honeycombbody, depositing a liquid adhesive at the portion of the honeycomb bodycorresponding to the bonding portion over the full axial length of thehoneycomb body outer layers by making the portion of one or both endfaces of the honeycomb body corresponding to the bonding portion overthe full axial length of the honeycomb body outer layers contact thesurface of the liquid adhesive and having the adhesive sucked up alongcontact lines of the flat and corrugated foils; and (d) then, feeding abrazing filler metal in powder to the honeycomb body so as to have itdeposited at the portions where the adhesives have been applied ordeposited.
 2. A method of manufacturing a honeycomb body according toclaim 1, characterized in that the bonding portion over the full axiallength of the honeycomb body outer layers covers ⅓ or less of the radiusof the honeycomb body from its outermost layer toward the centerthereof.
 3. A method of manufacturing a honeycomb body according toclaim 1, characterized in that the portions of the flat foil or thecorrugated foil to which the adhesive is applied are the portionscorresponding to the wave tops of the corrugated foil.
 4. A method ofmanufacturing a honeycomb body according to claim 1, characterized byapplying the adhesive to the portions of the flat foil or the corrugatedfoil by making rolls covered with the adhesive on the surfaces contactthe flat or corrugated foil.
 5. A method of manufacturing a honeycombbody according to claim 1, characterized by depositing the liquidadhesive at the portion of the honeycomb body corresponding to thebonding portion over the full axial length of the honeycomb body outerlayers by making a porous body impregnated with the liquid adhesivecontact the portion of one or both end faces of the honeycomb bodycorresponding to the bonding portion over the full axial length of thehoneycomb body outer layers and, thus, having the adhesive sucked upalong the contact lines of the flat and corrugated foils.
 6. A method ofmanufacturing a honeycomb body according to claim 5, characterized inthat the porous body has an annular shape.
 7. A method of manufacturinga honeycomb body according to claim 4, characterized in that theviscosity of the liquid adhesive to be sucked up to the honeycomb bodyis lower than that of the adhesive to be applied by the rolls.
 8. Amethod of manufacturing a honeycomb body formed by winding a flat metalfoil and a corrugated metal foil in layers and brazing them at thebonding portion over the full axial length of the honeycomb body outerlayers, at a bonding portion which is located at one or both ends of thehoneycomb body, and/or at a bonding portion inside the honeycomb bodyover a cross section which is located away from one or both ends thereofin the axial direction, characterized by: (a) prior to winding the flatand corrugated foils in layers to form the honeycomb body, applying anadhesive to the portions to be brazed of the flat or corrugated foilcorresponding to the bonding portion inside the honeycomb body over across section which is located away from one or both ends thereof in theaxial direction and to the portion excluding the portion which islocated at the gas inlet end of the honeycomb body from the bondingportion over the full axial length of the honeycomb body outer layers;(b) then, winding the flat foil and the corrugated foil in layers toform the honeycomb body; (c) then, after winding the flat and corrugatedfoils in layers to form the honeycomb body, depositing a liquid adhesiveat the portion which is located at the gas inlet end out of the bondingportion over the full axial length of the honeycomb body outer layersand the bonding portion which is located at one or both ends of thehoneycomb body, by making the gas inlet end face of the honeycomb bodyadhere to the surface of the liquid adhesive and having the adhesivesucked up along contact lines of the flat and corrugated foils; and (d)then, feeding a brazing filler metal in powder to the honeycomb body soas to have it deposited at the portions where the adhesives have beenapplied or deposited.
 9. A method of manufacturing a honeycomb bodyaccording to claim 8, characterized in that the bonding portion over thefull axial length of the honeycomb body outer layers covers ⅓ or less ofthe radius of the honeycomb body from its outermost layer toward thecenter.
 10. A method of manufacturing a honeycomb body according toclaim 8, characterized in that the portions of the flat foil or thecorrugated foil to which the adhesive is applied are the portionscorresponding to the wave tops of the corrugated foil.
 11. A method ofmanufacturing a honeycomb body according to claim 8, characterized byapplying the adhesive to the portions of the flat foil or the corrugatedfoil by making rolls covered with the adhesive on the surface contactthe flat or corrugated foil.
 12. A method of manufacturing a honeycombbody according to claim 11, characterized in that the viscosity of theliquid adhesive to be sucked up to the honeycomb body is lower than thatof the adhesive to be applied by the rolls.
 13. A method ofmanufacturing a honeycomb body according to claim 1, characterized inthat the flat foil has corrugation and the wave height of thecorrugation is smaller than the wave height of the corrugated foil. 14.A method of manufacturing a honeycomb body according to claim 8,characterized in that the flat foil has corrugation and the wave heightof the corrugation is smaller than the wave height of the corrugatedfoil.